Answer:
<em>Net force = 21.12 N</em>
<em>angle for the force α = 45°</em>
Explanation:
<em>In this problem, we will take the left as the negative x-axis, the right as the positive x-axis, and the upward direction as the positive y-axis.</em>
The 20 N force to the left has an x component of -20 N, and y component of 0 N
The 35 N force to the right has a x component of 35 N, and a y component of 0 N
The 15 N upwards has an x component of 0 N, and a y component of 15 N
We resolve the forces into the x and y components.
for the x component Fx
Fx = -20 + 35 + 0 = 15 N
For the y component Fy
Fy = 0 + 0 + 15 = 15 N
Net force Fn = 

<em>Net force Fn = 21.21 N</em>
for the angle,


α =
1
<em>angle for force α = 45°</em>
Answer:
11.025 m
87.75 m
Explanation:
Time of flight(T) of a projectile = 2U(sin∅)/g
Where U = initial Velocity, g = acceleration due to gravity, ∅= angle of projection.
Make ∅ the subject of the the equation,
∅ = sin⁻¹[(T× g)/2U]
Where U = 15m/s, T= 3.0 s, g = 9.8 m/s²
∅ = sin⁻¹[(3 × 9.8)/(2×15)]
∅ = sin⁻¹(29.4/30)
∅= sin⁻¹(0.98) = 78.52°
Using the formula for maximum height of a projectile
H = U²sin²∅/2g
H = 15²(sin²78.52)/2 × 9.8
H = 225(0.98 × 0.98)/19.6
H = 216.09/19.6
H = 11.025 m
Range (R) = U²sin2∅/g
R = 15²sin(2×79.52)/9.8
R = 225(0.39)
R =87.75 m
∵ the building is = 11.025 m tall and the base of the building is 87.75m away from where the stone landed.
Mass of the object is given as

now the speed of object is given as

here we know that


now we will have

now we will have kinetic energy of the object as



now the power is defined as rate of energy
so here we can find power as


so above is the power used for the object
Answer:
Distance covered is: 45 meters
Displacement is 15 meters to the right of where he started
Explanation:
Notice that Brady has walk a path that looks like an incomplete rectangle of height 5 meters and length 25meters, although he actually didn't cover the full length (25 meters) when getting back to the point where he started (he made just 10 meters instead of 25 after the third turn right) See attached image.
Therefore, Brady's displacement is 15 meters to the right of where he started, and the total distance he covered is :
Distance = 5m + 25m + 5m + 10m = 45m